Zeroing in on Decarbonization(news.mit.edu)
news.mit.edu
Zeroing in on Decarbonization
http://news.mit.edu/2020/zeroing-decarbonization-nestor-sepulveda-0115
7 comments
Ontario, Canada is even further ahead, having eliminated coal completed by 2014. They botched much of it, with setting up bad contracts, which led to a lot of wasted taxpayer dollars. Even still, it shows it's possible and the outcome was fantastic. Complete elimination of smog days and far lower incidence of asthma cases.
They also export clean power to US markets at the border. We thank them!
> In work published last year in the journal Joule, Sepulveda and his co-authors made a powerful case for using a mix of renewable and “firm” electricity sources, such as nuclear energy, as the least costly, and most likely, route to a low- or no-carbon grid.
> Recognizing that “absolutes exist in people’s minds, but not in reality,” Sepulveda sought to develop a tool that might yield an optimal solution to the decarbonization question.
The second part, I think, is very important to keep in mind when discussing whether or not to use nuclear to help solve the climate crisis. I'm not a big fan of nuclear, but if deploying huge amounts of it is what it takes to get us to zero carbon emissions by 2050, I'm for it. Yes, nuclear has its risks, and it's not renewable, but I think it would be worth pursuing as a stepping stone to get us to net-zero emissions sooner, while we figure out how to power the entire world via truly renewable energy. IMO, the potential risks of failing to address climate change rapidly enough are much larger than the risks of wide-spread nuclear power.
> Recognizing that “absolutes exist in people’s minds, but not in reality,” Sepulveda sought to develop a tool that might yield an optimal solution to the decarbonization question.
The second part, I think, is very important to keep in mind when discussing whether or not to use nuclear to help solve the climate crisis. I'm not a big fan of nuclear, but if deploying huge amounts of it is what it takes to get us to zero carbon emissions by 2050, I'm for it. Yes, nuclear has its risks, and it's not renewable, but I think it would be worth pursuing as a stepping stone to get us to net-zero emissions sooner, while we figure out how to power the entire world via truly renewable energy. IMO, the potential risks of failing to address climate change rapidly enough are much larger than the risks of wide-spread nuclear power.
Nuclear is renewable through uranium seawater extraction: https://www.pnnl.gov/news/release.aspx?id=4514
The uranium in seawater is same as uranium in the ground, not renewable.
Uranium in seawater is available in much larger quantities. We would not consume the amount of uranium over the next billion years even if we used nuclear for all of humanity's energy demands [1]. It is renewable in all but the most literal sense.
Uranium in seawater is the same as the hydrogen in the sun: it's not renewable. The hydrogen in the sun will eventually be fused to such an extent that no further energy will be released. There is no such thing as a renewable energy source because the laws of thermodynamics dictate that there is a finite amount of usable energy in the universe.
https://www.forbes.com/sites/jamesconca/2016/07/01/uranium-s...
Uranium in seawater is the same as the hydrogen in the sun: it's not renewable. The hydrogen in the sun will eventually be fused to such an extent that no further energy will be released. There is no such thing as a renewable energy source because the laws of thermodynamics dictate that there is a finite amount of usable energy in the universe.
https://www.forbes.com/sites/jamesconca/2016/07/01/uranium-s...
While I agree with you that it's virtually impossible for humans to use up the uranium in sea water at our current energy consumption rate, I think it's worth thinking about that if we had "unlimited" energy, we might use orders of magnitude more of it than we currently do.
That being said, for that to be an issue, we'd have to increase our energy consumption at least 1000x, and if we get to the point of using that much energy, it seems likely we'll also have advanced technologically to such an extent that we'll figure out another solution. It's just an interesting exercise to consider how what seems impossible today, might be totally routine in 10/100/1000 years.
That being said, for that to be an issue, we'd have to increase our energy consumption at least 1000x, and if we get to the point of using that much energy, it seems likely we'll also have advanced technologically to such an extent that we'll figure out another solution. It's just an interesting exercise to consider how what seems impossible today, might be totally routine in 10/100/1000 years.
Renewable in the context of energy policy means that it continuously renews on Earth on human timescales.
I agree that with uranium it's not really relevant in practice due to the large supply of it.
I agree that with uranium it's not really relevant in practice due to the large supply of it.
The typical slight of hand in such studies is to ignore long term storage, like hydrogen, and then conclude nuclear is needed instead of all-renewables.
A good argument against (long-term) storage could be that it does not exist yet. Not in commercial quantities at least. I think it would be accurate to state we can build nuclear in sufficient required TWh's right now, but we could not do the same for the storage we would need in a 100% renewable scenario.
More and more I think we just don't have the time for research anymore, and we should prioritize getting rid of carbon over going as green as possible. (Naturally I will agree that renewable is ultimately better than non-renewable nuclear.)
More and more I think we just don't have the time for research anymore, and we should prioritize getting rid of carbon over going as green as possible. (Naturally I will agree that renewable is ultimately better than non-renewable nuclear.)
Ah, the old "nothing ever happens for the first time" argument. A terrible argument, actually.
Hydrogen storage underground is a proved technology, already in use. Hydrogen pipelines exist. I'd argument the step to using hydrogen for long term storage is much more plausible than that nuclear will suddenly get off the failure curve where it gets more expensive over time rather than cheaper.
Hydrogen storage underground is a proved technology, already in use. Hydrogen pipelines exist. I'd argument the step to using hydrogen for long term storage is much more plausible than that nuclear will suddenly get off the failure curve where it gets more expensive over time rather than cheaper.
I'd love to see you support your argument!
I'm in favor of an 80/20 policy. 80% renewables, 20% nuclear.
The thing is, we're already at 20% nuclear. So the "debate" over it is largely a distraction/delay-tactic.
The thing is, we're already at 20% nuclear. So the "debate" over it is largely a distraction/delay-tactic.
But that doesn't work. If you go 80% renewable, there will be long periods where 100% of demand is being satisfied by the renewables (because they are so variable). This makes the economics of nuclear just horrible, as it needs to be selling its power at a good price most of the time to make ends meet. Nuclear and high penetration renewables just don't mix well.
You still need storage when you go 80% renewable, so any extra production by renewables can be used to generate hydrogen or charge batteries or something so that the nuclear plants can still sell their energy. It's not like they don't get any subsidies today, there is no reason why they shouldn't get any in the future.
It's just a question of what is cheaper or faster to achieve. I don't know enough details to say either way.
It's just a question of what is cheaper or faster to achieve. I don't know enough details to say either way.
Sure, nuclear could sell into storage, but most of the time that storage will be charged up with renewables, which are much cheaper. At best, nuclear will get rock bottom $ for that, much less than what they need to charge. So this doesn't save nuclear.
I don't think here are available storage solution for renewables and even if there was it would need to be a solution scalable without a risk of running out of resources to make the batteries.
Renewables are great but they work on the shoulders of nuclear/coal which need to pick up the load when there is no sun/wind.
Renewables feel like paying more for getting less with different but not necessarily less pollution issues.
Storage doesn't have to mean batteries. I'd have thought approaches like pumped hydro [1] could scale pretty well. I vaguely recall a similar story from a couple of years back that basically involved lifting giant concrete blocks.
[1] http://www.british-hydro.org/pumped-storage/
[1] http://www.british-hydro.org/pumped-storage/
If those solutions were viable at scale then countries like germany or england using lot of renewables and coal (gas or gb) would have been using them already.
They'd only be using them now if they cost less than gas + current carbon taxes.
The question is: at what level of carbon taxes would nuclear displace gas, vs. what level would renewables + storage displace gas. In the US, CO2 taxes would have to exceed $300/ton for new nuclear to displace gas CC baseload, and for intermittent applications the needed tax would be far higher.
The question is: at what level of carbon taxes would nuclear displace gas, vs. what level would renewables + storage displace gas. In the US, CO2 taxes would have to exceed $300/ton for new nuclear to displace gas CC baseload, and for intermittent applications the needed tax would be far higher.
The most scalable storage that I know of is making Hydrogen or Methane and using the existing infrastructure for strategic gas reserves to store it.
They should mix ok there are no fossil sources messing up the market in your 80/20 scenario:
If people are willing to pay enough for the 20% of time that nuclear stays in business. If not, we make do with just renewables.
The practical issue how how the nuclear plant sells electricity can be handled either with contracts (they could sell electricity to resellers in "one month of continuous production" types of units) or by running them in load-following mode, french/german style, whichever is more profitable.
In practice it seems fairly likely that there are many electricity applications where is pretty inelastic up to at least 10x current cost, so there will be demand for some amount nuclear power.
If people are willing to pay enough for the 20% of time that nuclear stays in business. If not, we make do with just renewables.
The practical issue how how the nuclear plant sells electricity can be handled either with contracts (they could sell electricity to resellers in "one month of continuous production" types of units) or by running them in load-following mode, french/german style, whichever is more profitable.
In practice it seems fairly likely that there are many electricity applications where is pretty inelastic up to at least 10x current cost, so there will be demand for some amount nuclear power.
No, what happens in the no-fossil scenario is the last 10-20% is handled by long term storage, in particular renewable hydrogen with combustion turbines. Sure, the round trip efficiency is lousy, but it's a hell of a lot cheaper than trying to shoehorn nuclear into covering that last 20%.
Is it? France generates over 70% of it's electricity from nuclear energy, at costs cheaper than most of its neighbors. Building up massive hydrogen storage and generation infrastructure is likely more expensive than building nuclear plants. The high overhead cost of nuclear is what makes it difficult to fund, the operating costs are minimal.
France's costs are opaque. They didn't separate military and civilian programs, and the information is now not available.
In any case, going forward, France's cost for new reactors are as exorbitant as in the US, if not worse. The new reactor at Flamanville has been a disaster.
In any case, going forward, France's cost for new reactors are as exorbitant as in the US, if not worse. The new reactor at Flamanville has been a disaster.
I found a source claiming that the total cost of their nuclearization program was 400 billion Francs (at 1993 inflation): https://www.world-nuclear.org/information-library/country-pr...
At an exchange rate of 1 franc (1993) to 1 usd (1993) and 1 usd (1993) to 1.77 usd (2019), this yields a cost of 120 billion dollars. Not bad to decarbonize the electricity supply of a country with a GDP more than 1/8 that of the US.
The nature of construction nuclear plants (and many other engineering products) is that that serial production is cheaper than the first several models, since the cost of development needs to be recouped. There are only 2 EPRs in operation and 4 in construction. By comparison, during the Messemer plan, 30 reactors of the same 900 MW design and 20 reactors of the 1300 MW design were constructed. This isn't counting reactors exported to different countries. Of course first 6 EPRs are going to be more expensive per unit as compared to serial runs in the dozens.
At an exchange rate of 1 franc (1993) to 1 usd (1993) and 1 usd (1993) to 1.77 usd (2019), this yields a cost of 120 billion dollars. Not bad to decarbonize the electricity supply of a country with a GDP more than 1/8 that of the US.
The nature of construction nuclear plants (and many other engineering products) is that that serial production is cheaper than the first several models, since the cost of development needs to be recouped. There are only 2 EPRs in operation and 4 in construction. By comparison, during the Messemer plan, 30 reactors of the same 900 MW design and 20 reactors of the 1300 MW design were constructed. This isn't counting reactors exported to different countries. Of course first 6 EPRs are going to be more expensive per unit as compared to serial runs in the dozens.
> This makes the economics of nuclear just horrible, as it needs to be selling its power at a good price most of the time to make ends meet.
Nuclear is not uneconomical just because it only needs to run 50% of the time. That would just mean the price is double; there's no technical obstacle there.
If twice as expensive is too expensive to compete with batteries (it is not), then nuclear is not economical period.
Nuclear is not uneconomical just because it only needs to run 50% of the time. That would just mean the price is double; there's no technical obstacle there.
If twice as expensive is too expensive to compete with batteries (it is not), then nuclear is not economical period.
Twice as expensive is possibly not too expensive to compete with batteries for LONG TERM storage. It's far too expensive to compete with batteries for diurnal load leveling. DC coupled batteries are already helping solar displace gas in the US west, for example, at price points nuclear can only dream of.
Renewables + batteries, and + hydrogen for rare lulls/seasonal storage, will leave no place for new nuclear. The system will optimize out to 0% nuclear, once existing nuclear plants are gone.
Renewables + batteries, and + hydrogen for rare lulls/seasonal storage, will leave no place for new nuclear. The system will optimize out to 0% nuclear, once existing nuclear plants are gone.
IMO people, even experts, still hugely underestimate the importance of solar to long term storage. Utility solar is very uncommon in snowy parts of the US, but it's the only place you can reasonably generate winter power.
The optimum winter angle in Massachusetts is just 24 degrees from vertical! That angle is so crazy steep that it can't possibly collect snow, but it generates several times more power than the rooftop panels that make up ~80% of MA solar. Since the total sunlight is 3.5x weaker in winter and demand is much higher, that's hugely important.
The darkest winter months between October to February (~4 months total where insolation is ~1/2 annual average) would mean virtually no solar if MA does not build utility scale plants. Nuclear and wind would be flat out the only ways to supply that without emitting CO2. However, if panels are angled for winter use they can easily outcompete nuclear. Nuclear running 4 months per year would cost 3x as much as normal. Overbuilding solar by 3x and angling it at 24 degrees would cost over 3x as much and generate less than the nuclear (because of cloudy days), but all that power would be available year-round at no extra cost. The amount of storage required would be almost the same, since it only needs to account for the shorter length of the day.
The optimum winter angle in Massachusetts is just 24 degrees from vertical! That angle is so crazy steep that it can't possibly collect snow, but it generates several times more power than the rooftop panels that make up ~80% of MA solar. Since the total sunlight is 3.5x weaker in winter and demand is much higher, that's hugely important.
The darkest winter months between October to February (~4 months total where insolation is ~1/2 annual average) would mean virtually no solar if MA does not build utility scale plants. Nuclear and wind would be flat out the only ways to supply that without emitting CO2. However, if panels are angled for winter use they can easily outcompete nuclear. Nuclear running 4 months per year would cost 3x as much as normal. Overbuilding solar by 3x and angling it at 24 degrees would cost over 3x as much and generate less than the nuclear (because of cloudy days), but all that power would be available year-round at no extra cost. The amount of storage required would be almost the same, since it only needs to account for the shorter length of the day.
I believe there was a study in Minnesota that concluded they could get to 70% of electric demand before it made sense to start adding storage, by overbuilding and curtailing solar, and by installing some of it at winter angles. I suspect bifacial solar also makes a lot of sense there.
A consequence of this will be that power will become very cheap much of the time. If you can consume power intermittently you'll be in a sweet spot.
A consequence of this will be that power will become very cheap much of the time. If you can consume power intermittently you'll be in a sweet spot.
I wish we did less modelling and more shutting down coal plants in favor of basically anything else.
Not snarky: when was the last time you called your utility to tell them you demand renewables? Or your state (for renewable mandates) and federal (national policy) Congressional reps? Protest at a coal plant?
Wishing is cheap, action pays the bills. I do all of the above. And there are signs of progress. The federal gov approved one of the largest PV plants in the US for California. Nevada is prepping for a 1.2GW PV facility with 600MW of storage.
Utility won’t switch off fossil fuels? Get rooftop solar and capture every damn incentive you can, or convince your local government to form a coop or muni utility to source clean power with a PPA at scale.
Wishing is cheap, action pays the bills. I do all of the above. And there are signs of progress. The federal gov approved one of the largest PV plants in the US for California. Nevada is prepping for a 1.2GW PV facility with 600MW of storage.
Utility won’t switch off fossil fuels? Get rooftop solar and capture every damn incentive you can, or convince your local government to form a coop or muni utility to source clean power with a PPA at scale.
If you're in any of these states/regions in the US you can opt-in to 100% renewables via a third-party-supplier:
https://cleanchoiceenergy.com/how-it-works/areas-we-serve/
If you're in a state that has a "community solar" program you can also join/opt-in to a project. Here's a company that exists to put investors in solar projects together with subscribers:
https://solstice.us/
https://cleanchoiceenergy.com/how-it-works/areas-we-serve/
If you're in a state that has a "community solar" program you can also join/opt-in to a project. Here's a company that exists to put investors in solar projects together with subscribers:
https://solstice.us/
[deleted]
It's easy in many states to pay for a "renewable" energy plan. In practice this means that your energy still comes from the same sources, but your utility purchases renewable energy credits from other solar and wind providers elsewhere in the country and "retires" them. This adds a small amount per-kWh to your bill, but in practice it's still dirt cheap. The problem is that I don't know if the prices are high enough to incentivize providers to actually build out renewable energy sources, or if this just makes people feel good.
When did anyone called a large company to ask them to operate differently ? and succeeded into being heard ?
“Hi regulated utility, I’d like to pay more for a premium product that your government overseers will have no problem with your providing.” :)
Less jokingly, actions like contacting a company (especially as a customer or as a potential customer) is more effective then you think- companies want to keep their customers happy and it’s pretty well assumed that one customer complaining means many more (probably thousands) thinking the same thing.
Less jokingly, actions like contacting a company (especially as a customer or as a potential customer) is more effective then you think- companies want to keep their customers happy and it’s pretty well assumed that one customer complaining means many more (probably thousands) thinking the same thing.
[deleted]
I get my electricity from a company that sells greenwashed energy and wrote a local politician and a MEP about renewables. I unfortunately don't have a roof where I can put panels as I rent an apartment.
You’re still doing your part! Want to run for office? I don’t think I can contribute as a US citizen to your campaign, but I’ll do the legwork.
I was a representative for my school in the student's council and nearly died in the sessions there, so I don't think I have what it takes to become a politician.
I believe in you. To get better at something, you must first suck at it. Your heart is in the right place, and that’s most important. Please consider running in the future!
A fee and dividend system[1] so the price of emission is actually included in the price of products is pretty damn important too. As is, it's only hippies and governments that are helping - with that system all companies and consumers would be incentivized to help cut emissions too.
[1] https://en.wikipedia.org/wiki/Carbon_fee_and_dividend
[1] https://en.wikipedia.org/wiki/Carbon_fee_and_dividend
Here is the referenced article if anyone is interested: https://www.dropbox.com/s/kj3ny5wk93bxj44/Sepulveda%20et%20a...
It's not enough to reach zero on carbon emission. There is way too much in the air already that we need to get out of it and somehow bind it to the (sub)surface of our planet to keep it out. And we need to find a way to do that on scale and in an economical viable way or it will never happen.
I saw 3 interesting diagrams on Wikipedia that basically tell a big part of the story.
* https://en.wikipedia.org/wiki/List_of_countries_by_carbon_di... * https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(nomi... * https://en.wikipedia.org/wiki/World_population
Turns out that the 3 countries who make up for the biggest share in greenhouse emissions are:
* China * The United States * India
Moreover, this graph (a) tells you that the U.S. has the highest C02 emissions per capita whereas India has the lowest CO2 emissions per capita in 2017. Way lower then many developed countries such as the EU28. A Chinese individual have emitted less then a German or South-Korean citizen in 2017.
(1) https://en.wikipedia.org/wiki/List_of_countries_by_carbon_di...
The bigger story is in the 3rd graph: population per country as part of global population:
* China: 18.1% * India: 17.5% * U.S.: 4.24%
Every other country below the top-8 only constitutes less then 2% of the global population.
Now, you can draw a few quick conclusions from that.
The total energy consumption in China is far less driven by individual consumption, but is more a factor of the total population. Lots of small consumers drive consumption towards a heck of a big number. Coal is the obvious answer as far as the Chinese are concerned because it provides a cost efficient way of scaling energy production to cater to 18.1% of the World's population.
Moreover, China isn't a particular rich country if you simplify things and use GDP per capita as a metric. Most of the people are relatively poor by Western standards, so their footprint in terms of how they live and consume isn't anywhere near what it is in Europe or North America.
You'd see the exact same dynamic at play in India.
As far as China and India are concerned, they will keep preferring coal unless clean solutions that could cater to the same vast demands become equally or more cost effective and scalable such that they can easily replace coal.
Then there's the U.S. with only 4.24% of the world's population, it manages to end up in the top-3 of most polluting countries, right after China and before India. Moreover, an American seems to have emitted twice the amount of CO2 as a Chinese person did in 2017. And finally, Americans are part of the top 10 richest individuals in the world if you look at GDP per capita.
Here you're looking at a different problem: individual consumption rather then total population. Whereas China and India can't readily reduce energy consumption because of their large population, the U.S. can easily reduce it's huge dependency on energy if individual consumption can be radically reduced.
The big hurdle here is that the biggest consumers of energy are those that fear they will have the most to lose: quality of life through existing conveniences and affordances that they feel will go away because they aren't sustainable. At this point, the whole debate often turns emotional and ends up in yak shaving or bike shedding.
The only other pathway for the U.S is similar to China and India: find a cost effective clean source of energy that can easily replace fossil fuels such as coal.
I would put this moral conundrum in front of you: If drastically cutting back emissions through a better management of personal consumption is clearly within your power and can be achieved today; then why refrain from doing so and passing on the responsibility to energy producers?
This doesn't just apply to the U.S. but to any country with significant CO2 emissions per capita, but it needs to be pointed out that countries with a small fraction of the global population with a high CO2 emission number per capita are those that can and will have the biggest impact on the problem, which contrasts seriously with countries in the opposite situation.
Of course, I understand that my whole expose ignores many, many other complexities that affect the balances such as global emission trade, global transportation and global trade (import/export).
My main point was to demonstrate why seemingly irrational decisions elsewhere in the world - such as investing in even more coal-based power plants - are driven by very different regional economics; and that battle cries such as "reduce carbon dependency" are blanket statements you can't impose everywhere in the world without adjusting it's meaning to the local or regional context.
* https://en.wikipedia.org/wiki/List_of_countries_by_carbon_di... * https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(nomi... * https://en.wikipedia.org/wiki/World_population
Turns out that the 3 countries who make up for the biggest share in greenhouse emissions are:
* China * The United States * India
Moreover, this graph (a) tells you that the U.S. has the highest C02 emissions per capita whereas India has the lowest CO2 emissions per capita in 2017. Way lower then many developed countries such as the EU28. A Chinese individual have emitted less then a German or South-Korean citizen in 2017.
(1) https://en.wikipedia.org/wiki/List_of_countries_by_carbon_di...
.svg){kind=link}
The bigger story is in the 3rd graph: population per country as part of global population:
* China: 18.1% * India: 17.5% * U.S.: 4.24%
Every other country below the top-8 only constitutes less then 2% of the global population.
Now, you can draw a few quick conclusions from that.
The total energy consumption in China is far less driven by individual consumption, but is more a factor of the total population. Lots of small consumers drive consumption towards a heck of a big number. Coal is the obvious answer as far as the Chinese are concerned because it provides a cost efficient way of scaling energy production to cater to 18.1% of the World's population.
Moreover, China isn't a particular rich country if you simplify things and use GDP per capita as a metric. Most of the people are relatively poor by Western standards, so their footprint in terms of how they live and consume isn't anywhere near what it is in Europe or North America.
You'd see the exact same dynamic at play in India.
As far as China and India are concerned, they will keep preferring coal unless clean solutions that could cater to the same vast demands become equally or more cost effective and scalable such that they can easily replace coal.
Then there's the U.S. with only 4.24% of the world's population, it manages to end up in the top-3 of most polluting countries, right after China and before India. Moreover, an American seems to have emitted twice the amount of CO2 as a Chinese person did in 2017. And finally, Americans are part of the top 10 richest individuals in the world if you look at GDP per capita.
Here you're looking at a different problem: individual consumption rather then total population. Whereas China and India can't readily reduce energy consumption because of their large population, the U.S. can easily reduce it's huge dependency on energy if individual consumption can be radically reduced.
The big hurdle here is that the biggest consumers of energy are those that fear they will have the most to lose: quality of life through existing conveniences and affordances that they feel will go away because they aren't sustainable. At this point, the whole debate often turns emotional and ends up in yak shaving or bike shedding.
The only other pathway for the U.S is similar to China and India: find a cost effective clean source of energy that can easily replace fossil fuels such as coal.
I would put this moral conundrum in front of you: If drastically cutting back emissions through a better management of personal consumption is clearly within your power and can be achieved today; then why refrain from doing so and passing on the responsibility to energy producers?
This doesn't just apply to the U.S. but to any country with significant CO2 emissions per capita, but it needs to be pointed out that countries with a small fraction of the global population with a high CO2 emission number per capita are those that can and will have the biggest impact on the problem, which contrasts seriously with countries in the opposite situation.
Of course, I understand that my whole expose ignores many, many other complexities that affect the balances such as global emission trade, global transportation and global trade (import/export).
My main point was to demonstrate why seemingly irrational decisions elsewhere in the world - such as investing in even more coal-based power plants - are driven by very different regional economics; and that battle cries such as "reduce carbon dependency" are blanket statements you can't impose everywhere in the world without adjusting it's meaning to the local or regional context.
But! Nuclear takes ages to build, advanced nuclear even longer, and gas+capture is deployed almost nowhere because there's no negative carbon pricing for it.
So perhaps they are viable in the long term. For 2020? Countries need to be accelerating their wind and solar rollouts and using them to push carbon-emitting sources down the dispatch order as far as possible.
The UK is surprisingly far ahead on this, having eliminated coal for most of the year and running a gas/nuclear/wind mix currently at 30% wind.